On Oct 1, 2012, at 10:27 AM, David Winsemius wrote: > > On Oct 1, 2012, at 9:48 AM, stephenb wrote: > >> The error is just a misleading error message. loading the data produced >> column sdate as >>> str(prostate) >> $ sdate :Classes 'labelled', 'dates' atomic [1:502] 2778 2820 2933 2999 >> 3002 ... >> .. ..- attr(*, "format")= symbol ddmmmyy >> .. ..- attr(*, "label")= chr "Date on study" >> >> prostate$sdate <- as.Date(prostate$sdate,origin="1970-01-01") # fixes the >> problem and 'describe' runs >> >> just as a comment: maybe the R dataset should have sdate as a Date class. >> > > What "R dataset"? From what package? > > And it's already a "dates"-classed variable.
Not only that, but there is a message at the top of Harrell's Datasets page that says: "For R users of the prostate dataset, put library(chron) into effect to handle date variables. A simpler approach is to just convert the one date variable to the built-in R format by running the command prostate$sdate <- as.Date(prostate$sdate)." -- David Winsemius, MD Alameda, CA, USA ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.